Art of treating starch materials.



l A. P. ANDERSON. ART 0F TBEATING STABO MATERIALS.'

'ArrLIoATIox rxmzbvun. 24, 1901. w

Patented Aug. 20, 1912.

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.J7/runder P nderon ymaterial is puffedl or inflated several times' UNITED STATES PTENT. OFFICE.

ALEXANDER P. ANDERSON, 0F CHICAGO, ILLINOIS.

ART 0F TREATING STARCH MATERIALS.

.Specification of Letters Patent.

Patented Aug. 20, 1912.

Application tiled April 24, 1907. Serial No. 370,004.

To all 'whom t may concern.

Be it known that I, ALEXANDER Py ANDER- lson, a citizen of the United States, residing at Chicago, in the county of Cook and State vof Illinois, have invented new and useful Improvements in the Art of Treating Starch' Materials, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing,'forming a part of this Specification.

My invention relates to an improvement in the 'art of treating starchlmaterial and has for its object a new process for the production of pulled or swelled starch-materials, such as starch, cereal grains of all kinds, whether hulled or unhulled, and other seeds or kernels containing starch.y

. In my United States Patent No. 707,892, dated August 26, 1902, I have described a process of swelling starch-materials. According to such process, the material in a substantially airdry condition is heated yunder vpressure,.which when suddenly reduced causes the moisture contained in the material to burst into steam, whereby the its original volume. It will be observed that by `this vprocess the puffing is accomplished with steam derived solely from the natural moisture of the material under treatment. Now, during the practice of the said process with. cereal grains, I discovered that by injecting steam'into the cylinder at a certain stage of theprocess, so as to subject the grain in the cylinder to the action of the steam, I obtained far better results. For example, when the material is in a practically anhydrous condition, or when it contains an amount of moisture that is insufficient for its proper swelling or pulling, the necessary percentage `of moisture may be readily supplied according to my new method by the injection of steam into the cylinder containing the material under treatment. In this connection I furthermore discovered that the best and most satisfactory results are obtainable by the use of dry steam, preferably steam in a superheated condition, as will hereinafter be fully explained. c I In carrying out my new process in the preferred manner, the material under treatment is heated in a closed receptacle which is preferably rotated, provision being made for the admission of steam into and withdrawal of`vapors from the receptacle, and for the suddenfreduction of pressure surrounding the material for the purpose of pulling' or swelling the same.

In ltheaccompanying drawings-I show one form4 of apparatus suitable for treating starch materials iny accordance with the herein described process.

Figure l is a side view of. the piping together with a; longitudinal sectional'elevation of the drum-support in the oven, the latter being indicated in dotted lines; Fig. 2 is a rear end View of the oven; Fig. 3 shows the drum in charging and dischargmg positions, thelatter position being indicated in dotted lines. Fig. 4 is a sectional view of the rear end of the drum; and, F ig. is a section of the drum on the line 5 5 of Fig. 4.

The material to be treated is put into a drum 2, mounted upon a suitable car capable of being rolled about and brought to the various parts of `the apparatus for handling. yT he car consists of two side members 3, 3, having a trunnion 4 extending therebetween `at the rear end; a shaft or axle 5 connects the forward ends of said members.

LSmall wheels or rollers 6 are mounted outside of the members 3, upon the projecting ends of trunnion 4, and shaft The cars run on a track 7 within the oven consisting of four rails fastened to the inside of the cage 8. At each end of the oren is a ring 9 having teeth outside forming a gear, which meshes with another gear l() adapted to rotate the cage. The gears 10 and rollers 11 support the cage and inclosed drum, in addition to turning it by any suitable power applied to one of their supporting shafts outside of the oven. After the drum has been run into the oven, a steam-connection is made at 12, thus admitting steam to the flattened pipe 13 inside of the drum. The steamyescapes into the drum through numerous holes 14 in the pipe, said holes becoming more frequent in proportion to the drop in pressure as the steam advances.

By means of' gears 9 and 10 the cage containing the drum is rotated slowly during the heating.. Rotation is permitted by the stufling box 12a which at the same time maintains the steam-connection. The arrangement of the piping shown is as follows: 15, 15", 15, 15d and 15e are valves; 16 is a pressure gage. By opening valves 15b and 15a, and closing valves 15d and 15C, theA steam is bypassed around the drum. By

valve-manipulation the conditions o closing valves 15b and 15d, and opening 15, the pressure in the drum may be brought to any desired point, as shown by gage 16. To

reduce the pressure in t-he drum, valve 15c may by gas. d The lid 18 of the drum is clamped tightly closed, a suitable soft-metal gasket being rovidecl to cause an airtight connection, when the drum is in the horizontal position in the frame. In order that the heating may not unseal the lid, I prefer to make the drum of bronze, or some material having a higher coefficient ofexpansion vthan the side members of the frame. l

` To remove the drum from the oven after -the heating, valve 15E is closed, the drum is disconnected at 12; and is run out Aof the oven to a raising and lowering mechanism suitably connected with the drum through the arm 17. By means of this mechanism the drum is lowered about the shaft 4 as a pivot, as indicated in dotted lines in Fig. 3.

e The lid 18, previously held shut by the roller sisted by gravity,

' to they drum or cylinder.

19, suddenly flies open from internal pres sure, and the contents are discharged, as-

and at the Sametime puff up in size. The puffed product is discharged with considerable force into a receptacle or cage-many times the volume of the drum and adapted to confine it. In charging, the drum is raised by the same armor screw' 17 until it tilts upwardly, when the material to be treated may be fed into the drum.

Itwill be observed that in Fig. 1 the pipe 20 passes for its greater length through the upper part of the oven. The purpose of this arrangement is to cause superheating of vthe steam during its passage through said pipe For the sake of clearness and simplicity, Ihave omitted to show the right end of said pipe 20 'con nected with the source of steam supply, inasmugh as such a connection is entirely obvious to any one skilled yin the art. Then again,` although I have shown the pipe 20 as a single pipe, it is to be understood that the pipe 20 may be coiled back and forth in the upper part of the oven in order to provide a longer passage for the steam through the o ven. Of course any other suitable form o f steam superheater may be employed, the one shown being for the sake of illustration only. f

For the purpose of making a full and complete disclosure of my invention, I shall describe in detail the preferred manner of carrying out the process, at. the same time ciple of the invention.

A suiicient quantity ofthe material to be treated-as, for instance, rice, either hulled or unhulled-is poured into a drum or cylinder, preferably in an air-dry condition. Enough rice is used to fill the cylinder from one-half to three-fourths. Thecylinderis now sealed so as to be air-tight, or substantially so, and is then run into the oven where it is heated while being rotated. It is understood that the 'cylinder may' be either cold or hot before the rice is pouredv into it for treatment. '.1

stantially air-dry condition contains a certain amount of moisture, say from 10 to 20%, the first eect ofthe heating is to evaporate or drive off a portion of this moisture so that the air confined in the cylinder becomes saturated with water vapor or steam. As soon as the temperature of the rice reaches 10 0 vdegrees C., of soo-n thereafter, pressure begins to form inside ofk the cylinder, the pressure increasing correspondingly with the increase of temperature. The

17 5 to 27 5 degrees C.so that any pressure up to 100 lbs. or `more maybe obtained within the cylinder as a result of the heat applied to it. It is evident that during the treatment the ricefbeco-mes drier, due to the causes pressure in the confined space in the cylinder not occupied by the rice. When this space is large, as e. gv., when the cylinsay only one-fourth or one-third filled with it-thechance of the rice drying is still greater, becoming in fact anhydrous, or nearly so, as soon as pressure begins to deof the rice grains. The treatment 1s continued until' a pressure of from 10 to 110 lbs. develops within the cylinder, depending upon the color, flavor and cook that it is desired to give the finished product. Thus, when a whitish puffed rice isv desired, a pressure fof 10 lbs. is suflicient; and when a cream-colored or brownish puffed rice is desired, 110 lbs. pressure is sufficient to give it this added cook and temperature. This pressure within the cylinder .may nowbe reduced slowly, as by blowing off the confined atmosphere whereby all air is removed, together with any deleterious vapors arising from the grain. The blowing off is done slowly, as by opening the cylinder valve, and is continued until the pressure runs down to zero or only untila slight pressure reduction results. The blowing off may be continued for some time-say ten minutes or more; thus, when the rice contains about 20% of moisture and it is derealizing that variations may be made there-` in without departing from the scope or prin-A Owing to the factthat rice in its subtemperature of the cylinder should be about I conversion of its moisture into steam which der contains only a small amount of ricec' velop out of the` steam from the moisture 10 der shouldbe made sired to dry outlsome or all of this, it may be readily accomplished by continuing the blowing olf and drying until the grain contains any moisture 5 readily determined by practice. The blowing out of a part or all of the pressure that has developed within the cylinder during this heating is not essential to the fina] step of puffing, nor is it essential that the cylinperfectly air-tight during the heating and drying of the grain as has been described. Thus, the cylinder valve may be left open and thel steam or water vapor arising from' the rice grains during their heating inside of the rotating cylinder may be allowed to escape as soon as formed. In this case the rice grains lose all or nearly all of their moisture. In either case, the moisture that has been given ofi' from the grains isnow replaced by injecting steam into the cylinder, especially dry and preferably superheated, in order to .assure its absolute dryness, as well as to give the rice grains a higher temperature when this is desired. The steam thus injected is preferably at a pressure of 150 to 200 lbs. Enough of this steam is blown into thecylinder to produce a pressure of from 10 to 1 50 lbs.,preferably 150 lbs. when the cylinder valve is'closed. This steam may now be blown off slowly, in part or completely, by opening the cylinder valve, and thus the grain becomes again free from moisture to a greater or less degree. In this case,

however, steam is again injected up to a pressure of Iabout 140 lbs. This is preferably left in the cylinder for a short time-say from one-halfminute to five minutes-during .which time the cylinder is kept in continuous rotation so that all of the grains become exposed to the steamatmosphere now surrounding them. In .this way'the slight condensation of the steam on the surface, as well las on the inside of each rice grain, is uniform and even. `Due to the condensation of thesteam, on the grain, there occurs a slight falllof pressure within the cylinder. his, however, is only slight-say from 5 to 25.1bs. per square inch. As soon as the rice grains have received enough moisture `from the condensing steam to glve them a total moisture of about 10 to 20%,'the rice is suddenly discharged from the cylinder while under the maximum pressure, whereby a sudden and "practically instantaneous reduction of pressure is obtained. This sudden reduction .of pressure surrounding the grains causes the pressure within the interior of each kernel to assert itself and swell the rain to a large size, pulling it by steam in ation,'render1ng it cellular, and givingit all Athe 4characteristics of' puffed r1ce.

The aimthroughout the whole process is 65 to keep the grain under treatment as nar as percentage desired,

Such moisture percentage may any exists, as by leaving the cylinder valve open and thus allowing the excess moisture to escape. The final or puffing pressure, however, is obtained by injecting steam to a pressure of 7 5 to 150 lbs., it having been deter-mined by practice that in order" to puff any Cereal grain, a pressure inside of the grain or kernels of from'75l to' 150 lbs. per square inch is necessary. Steam may be injected at any time and any number of times and the pressure thus formed reduced by blowing off, but it has been found that it is preferably injected after the air-dry grain in the cylinder has become heated to` a temperature varying from 115 to 180 degrees C.,

or to a pressure of from 10 lbs. to 110 lbs.

per square inch. This is necessary in order that the steam injected may not cause too much condensation on thegrains and thus prevent their perfect stirring, as well as cause them to stick together.

have discovered that by the use of ordinary or wet steam, the condensation on the grains is more Iorless irregular, for the reason that the moisture carried into the cylinder by the steam is not distributed evenly over the grains but is liable to condense m Certain places more than in, others.. Iurthermore, wet steam is apt to introduce into the cylinder undesirable quantities' of dripping water which causes many of the grams or particles to stick together in lumps, thus preventing the even and perfect pufiing of the individual grains. What is known J as saturated steam answers the purpose well when such steam does not drip water upon entering the cylinder. Small particles of moisture, nearly always present in saturated steam, condense evenly on the surface of the grains, with the result that the materlal pre'- serves a desired crispness and imperviousness due to the formation of a coating that covers theent-ire puffed grain, seed or starchlump. In general, however, I have found that the most satisfactoryrresults are obtained by the use of superheated steam, which, having the-characteristic properties of a gas, lprevents local and uneven. condensation upon entrance into the cylmder, but condenses on the grains in infinitesimal quantities and with great uniforrn1ty, at the same time causing steam-saturatlon of the whole grain or lump of starch-material. Also, such superheated steam adds to the -the 'cylinder pressure-gage.

material a certain amount of heat, whereby l a greater sterilizing as well as'cooking elfect takes place. l

It is not essential that the cylinder should j be discharged as soon as the steam for the puffing of the grain has been injected; thus, whenxa greater cooking of the grain is desired the treatment may be prolonged after the steam is injected, especially when not enough steam is injected to cause puiiing, until the pressure increases to pulling pressure.

It is evident that the injected steam not only fills the space unoccupied bythe rice within the cylinder but also saturates each grain of rice at the pressure indicated on- Each rice grain "has thus anL internal pressure as well as an external one. When the external pressure is suddenly or instantaneously removed, the internal pressure puffs the grain, since the steam and moisture inside of the grain cannot escape fast enough on account of the grain having been rendered resistant to the rapid escape of its moisture. Hence the whole rice kernel is puffed, increasing its volume evenly from four to fifteen times. It is apparent that when paddy rice is treated as above described, the hulls are thrown before reaching loff from the' expanding kernels.

AInasmuch as'theY hulls do notthemselv'es expand, they are now too small to inclose the kernel after it has become increased in volume as stated.

In case it. is desired to subject wheat to the treatnient above described, the wheat is well cleaned and scoured so as to remove all its dust andi the outer epidermal layer of the grain but not any of the nutritive bran portion, since it is designed to retain in the berry all of its nutritive portion after puiing. Enough of this wheat in its substantially air-dry condition is poured intothe cylinder to fill it from one-half to threefourths. It is then treated in a manner similar to that of rice above explained, or it may be treated as follows: The cylinder with the grain is preferably'sealed air tight. It is then run into the oven kept at a temperature of about 290 degrees C., and its rotation begun. After about ten minutes the cylinder-gage begins to show pressure, and after about thirty minutes the pressure has reached about 40 lbs. per square inch. Now. without any blowing o of this pressteam superheated las high as 500 degrees, may safely be injected into the cylinder, it being evident that the steam in passing from the superheater loses much of its heat before reaching the grain or starch material in the cylinder, whereby undue heating of the material is prevented. It is, of course, apparent that one may einploy any approved form of well-known superheater used in connection with steam- 4boilers and the like. For this reason I have deemed it unnecessary and superfluous to show in the drawing any particular type of superheater. The superheated steam is allowed to liow into the cylinder until the gage shows about 145 lbs., when the steam injection valve is closed, leaving this` pressure inside of the cylinder. The latter is now allow-ed to rotate within the oven about one minute longer, during which time its pressure will fall slightly to about 140 lbs., such drop in the pressure being due to the steam condensing slightly on the wheat berries. The cylinder is now stopped, disconnected and run to the discharge machine, and the lid suddenly opened to allow the confined steam and wheat-to be discharged from it like shot from a gun. The wheat berries come out puffed and greatly increased in Size, as well as in a substantially air-dry condition. Other cereal grains, c. g., Kaf'ir corn, millet, corn, barley and the like may be similarly treated and puffed.

Cereal grains treated as herein set forth have essentially thecharacteristics o f the cereal products described and claimed in my United States Patent No. 756,212, dated Aug. 2, 1904, while starch thus. treated presents a product such as claimed in my United States Patent- No. 769,289.

The above described process of puffing starch materials by the injection into the cylinder of dry steam, especially superheated steam, is applicable n otonly to starches and cereal grains of all kinds, but is equally applicable to the puffing of such starch-coni taining nraterials as spaghetti or macaroni in its various forms,`as, for example, alphabet macaroni, stick macaroni, star macaroni, and the like. The product obtained. by the puffing of these last-mentioned-materlals according to my improved substance be the same as that claimed in Sl1I`,'eXCpt`to blow out any condensed water my co-pending application Serial No. th1t-may have formed in the cylinder con- 116,27 9, filed July 19, 1902; `Patent No. nections, the steam injection valve is opened 87427 9 Dec. 17, 1907. e

and steam is injected into the cylinder at a pressure of 150 to 200 lbs. This steam just the cylinder is passed through a steam superheater, e. g., a heated coil of sufficientlength set above the burners inside of the oven used for heating the rotatin cylinder, such steam superheater givinto the cylinder,

ing t e Steam a temperature varying from about 185 to 500 degrees. I have found that It will be apparent from the aboye description, that the all-important step in this mv new and improved process in ythe .treatment of starch materials, is the subjecting of the mate-rial in a substantially air dry condition to the action of steam, especially dry and preferably superheated steam, injected for the purposes above set forth. Wherefore, in the appended claims method would in Which consists in con I cover broadly this step of thus subjecting the material under treatment to the action of steam, especially dry and preferably superheated steam, injected at the proper time into the cylinder containing the material.

Inasmuch as it is not necessary to have the drum air-tight during the treatment of the material, as hereinbefore fully explained, I would have it understood that by the term closed receptacle as used in some of the appended claims, I mean a receptacle which may or may not be air-tight according yas it is desired to carry out the process with. or without extreme pressure within the receptacle,-all as previously set forth.

' Having thus described my' invention, what is claimed as new and desired to se- 'cure byL'etters Patent of the United States 1s:-

1. The process disclosed which consists in confining lumps -or grains of starch or starch-containing material in a closed receptacle and injecting steaminto the receptacle to generate an internal pressure within the lumps or grains, and then suddenly reducing the pressure within the receptacle, whereby the grains or lumps, due. to their internal pressure, become pulfed or leX- panded.

2. The process disclosed which consists in vconfining lumps or grains of starch or starch-containing material in a closed receptacle and injecting superheated steam into the receptacle to generate an internal pressure within the lumps or grains considerably in excess of atmospheric pressure, .and then suddenly reducin the pressure within the receptacle, where y the grains or lumps, due to their internal pressure, become puffed or expanded.

3. The process of uiiing cereal grains ing the same in a closed receptacle and injecting steam into said receptacle until and whereby an internal pressure is created wlthin the grains considerably in excess of atmospheric pressure, and Vthen suddenly reducing the pressurev within the receptacle, whereby the grains become puffed or expanded.

4. The process of 1putting cereal grains which consists in con ning such grains in a substantially alr-dry condition in aclosed receptacle and lnjectmg superheated steam into said receptacle until and whereby an internal pressure is created within the grains considera-bly in excess of atmospheric pressure, and. thensuddenly reducing the pressure within the receptacle, whereby the grains become puied.

5. The process of treating cereal grains which consists in heatingthe substantiallyy the receptacle, whereby thev grains becomey puffed 6. The process of treating cereal grains which consists in heating the substantially air-dry ,grains in a closed receptacle, then injecting super-heated steam into the receptacle to quickly increase the pressure within and the temperature 'of the individual grains, and then suddenly reducing the pressure within the receptacle, whereby the grains become puffed.

7 The process of treating cereal grains, which consists in heating substantially airdry grain in a closed receptacle, meanwhile agitating or tumbling the grain, until pressure has developed therein, then reducing the pressure to reduce the moisture content.

of the grain, then injecting steam until a pressure of about 75 to 150 pounds per square inch has developed within the receptacle, whereby the pressure within the individual grains is increased, and then suddenly reducing this grains become puffed. l

The process of treating cereal grains, which consists in heating substantially airdry grain in a closed recepacle, meanwhile agitating or tumbling the grain until pressure has developed therein, then slowly reducing the pressure to reduce the moisture content of the grain, the injecting steam into the receptacle to develop an internal Dressure of square inch within the individual grains, and then suddenly reducing the pressure within the receptacle, whereby the grains become puli'ed.

9. The process of treating cereal grains, which consists in tumbling and heating the substantially -air-dry grain in a closed receptacle until pressure has developed therein, then slowly reducing the pressure to reduce the moisture content of the grain, then injecting superheated steam into the receptacle to develop an internal pressure of about 75 to 150 pounds per s uare inch within the individual grains, an then suddenly reducingy the pressure within the receptacle, whereby the grains become puffed.

In witness whereof, I have hereunto subscribed my name in the presence of two witnesses.

ALEXANDER P. ANDERSON.

Witnesses:

A. A. THOMAS, AC. L. HOPKINS.

about 75 to 150 pounds perl pressure, whereby the Correction n Letters Patent No. 1,

'It is herebyr certified that in Letters Patent' No. 1,035,835, granted August 20,

1912, upon the application of Alexandery Anderson, of Chicago, li1inois,rfor an improvement in The Art of Treating Starch i\/1aterials,7 errors appear inthe printed specification requiring correction as follows: Page 1, line 68, for the Word oven Aread arrange-ment shown n Fig. A1,' page1, lines 65 and 66, after the vgord degrees insert the abbreviation O. page 5, line 97, for the Word the7 read than; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the oase in the Patent Office.

Signed and sealed this 29th day of October, A. D., 1912.

[SEAL] i o. C. BILLINGS;

Acting Uommssz'oner 0f Patents. 

